fix for vnd.api+json content type using regex

openapi_tester/schema_tester.py

@@ -1,6 +1,7 @@
 """ Schema Tester """
 from __future__ import annotations
 
+import re
 from itertools import chain
 from typing import TYPE_CHECKING, Any, Callable, cast
 
@@ -89,11 +90,16 @@ def __init__(
             raise ImproperlyConfigured(INIT_ERROR)
 
     @staticmethod
-    def get_key_value(schema: dict[str, dict], key: str, error_addon: str = "") -> dict:
+    def get_key_value(schema: dict[str, dict], key: str, error_addon: str = "", use_regex=False) -> dict:
         """
         Returns the value of a given key
         """
         try:
+            if use_regex:
+                compiled_pattern = re.compile(key)
+                for key_ in schema.keys():
+                    if compiled_pattern.match(key_):
+                        return schema[key_]
             return schema[key]
         except KeyError as e:
             raise UndocumentedSchemaSectionError(
@@ -168,9 +174,10 @@ def get_response_schema_section(self, response: Response) -> dict[str, Any]:
             )
             json_object = self.get_key_value(
                 content_object,
-                "application/json",
+                r"^application\/.*json$",
                 "\n\nNo `application/json` responses documented for method: "
                 f"{response_method}, path: {parameterized_path}",
+                use_regex=True,
             )
             return self.get_key_value(json_object, "schema")